The studies on characteristics of magnetic memory signals of ferromagnetic component for double defect associated

Metal magnetic memory (MMM) testing technique is a novel testing method which can early test stress concentration status of ferromagnetic components. Adopting the combination method of experimental research and simulation analysis, and the influences of notch characteristics on magnetic memory signals were studied. In the experiment, the Q235 steel specimens with different defects were taken as the object of study, the mechanical characteristics of the static tension curve are studied, and the relationship between the magnetic memory signal with the tensile stress was studied. In the aspect of simulation analysis, under different tensile stresses, the distribution characteristics of stress and magnetic signal were simulation analyzed on different paths of double defect specimens, which is consistent with the test results basically. The results show that semicircular notch is more potential danger than V-shaped notch specimen; The normal component of magnetic flux leakage and gradient value in stress concentration of double associated notch specimen are no longer applicable for evaluating stress concentration degree of double associated notch. The conclusions are of great significance to the quantitative detection and further research of metal magnetic memory testing technology.